Feed pusher



Nox r. 27, 1945. c. s. KASPER 2,389,913

FEED .PUSHER Filed Sept. 22, 1943 INVENTOR A TTORNE Y5.

Patented Nov. 27, 1945 UNITED STATES PATENT OFFICE FEED PUSHER Cass S.Kasper, Grosse Pointe, Mich.

Application September 22, 1943, Serial No. 503,385

2 Claims.

The invention relates generally to automatic screw machines and it hasparticular relation to: a stock pusher for feeding bar stock into themachine.

As will be readily understood by those skilled in the art, stock pushingdevices are used in automatic screw machines for the purpose ofintermittently feeding the bar stock. Ordinarily, the bar stock used iseither round or hexagonal in shape and often it is substantially largein dimensions so that considerable force is required to move it,especially when the stock is long. While perhaps different types ofstock pushing devices have been employed in machines of this character,a rather well known type includes spring-like gripping fingers whichhave constant and strong friction engagement with the side surfaces ofthe stock. These devices will frictionally slide over the stock in onedirection without moving it owing to the fact that the stock is heldagainst movement and when the devices are reversely moved, themaintained frictional contact will advance the stock into the machine.Due to the fact that the frictional engagement is maintained on thestock during movement of the devices in both directions, it is apparentthat considerable wear must occur on the spring-like fingers and thattheir efiiciency will decrease accordingly.

One object of the invention is to provide an improved stock pushingdevice which will be more efiicient, more durable, and more practical inoperation, so that the cost of operation of the machine will bedecreased and its efliciency increased.

Another object of the invention is to provide a stock pushing devicewhich may be manufactured and assembled easily and inexpensively.

Another object of the invention is to provide an improved stock pushingdevice wherein in the idling movement of the device, wear thereonthrough engagement of the device with the stock, is minimized.

Another object of the invention is to provide an improved stock pushingdevice of the foregoing character, wherein immediate gripping of thestock by the device occurs upon reversing the movement when the stock isto be fed into the machine.

Other objects of the invention will become apparent from the followingspecification, from the drawings relating thereto, and from the claimshereinafter set forth.

For a better understanding of the invention, reference may be had to thedrawing wherein:

Figure 1 is a longitudinal, cross-sectional View, illustrating a stockpushing device constructed according to one form of the invention;

Fig. 2 is an end elevational View taken substantially along the line2--2 of Fig. 1;

Fig. 3 is a cross-sectional view on the order of Fig. 1 illustratinganother form of the invention;

Fig. 4 is an end elevational view taken substantially along the line 4-4of Fig. 3. I

Referring to Figs. 1 and 2, a stock pushing sleeve forming part of thestock pushing device' is indicated at H) and one end of this sleeve hasthreaded engagement, as indicated at H, with a reciprocatory member 12forming part of an automatic screw machine and which is adapted to bemoved during operation of the latter. On its inner periphery, the sleeveI0 is provided with a tapered secondary sleeve element M which isadapted to serve as a piloting element when a bar of stock isintroduced. For the purpose of moving the stock, rings l6 and I! areprovided within the sleeve and each of these at the top of the sleeveextends between a pair of projections it] and I 9 which are riveted tothe sleeve wall. These projections axially anchor the rings on thesleeve so that when the latter is moved to the right in the stockpushing operation, the rings necessarily must move with the sleeve.

Each ring is biased toward a tilted position by a spring element 2!having a small loop or eye.

22 intermediate its ends which is anchored on the sleeve by means of ariveted projection 23 located substantially opposite the projections l8and I9. Circumferentially, at each side of the projection 23, the springwire first extends in a circumferential direction along the innersurface of the sleeve, as indicated at 25, and then it is reverselyturned, as indicated at 25, so that the two portions 25 and 26 aredisposed in normally diverging relation. The free end of the portion 25is turned toward the center of the sleeve, as indicated at 21, so as toprovide a part adapted to contact the side of the ring 16. Fromv this itwill be apparent that the spring element includes two parts, eachcomprising the sections 25, 25, and 21,- with the spring anchoredbetween the two parts 25 by means of the loop ZZ and with the two ends2'! contacting the side spring so as to move it towards a radialposition and permit the bar to easily pass through. The spring urges thering to a position such that upper and lower portions of the ringcontact upper and lower sides of the bar and, since the bar in thisinstance is shown as of hexagonal shape, the corners of the bar willnormally be in contact with the upper and lower sides of the ring. Anyslight movement of the stock to the right tends to shift the ring topermit the stock to move through, but any tendency of the stock to moveto the left naturally tends to increase force of contact between therings and the upper and lower corners of the stock. This tendency of thering to obtain positive, binding engagement is accentuated by thesprings which normally are acting to urge them into binding relationwith the stock. Rings such as shown, which are circular in crosssection, are suitable for hexagonal bars in particular since the cornersof the latter will enable obtaining sufficient binding action betweenthe rings and the stock.

From the foregoing, it should be understood that when the stock is firstinserted, it may freely be moved through the rings to its approximateposition and then the stock may be moved in the same direction by movingthe sleeve If! to the right. Since the rings are instantly able to gripthe stock through forceful binding engagement, any advancing movement ofthe sleeve will instantly effect corresponding movement of the stock.Idling movement of the sleeve to the left allows the rings to slide overthe stock freely, but immediately upon reversed movement of the sleeve,the rings bind against the stock and move it.

The relative dimensions of the rings and sleeve are such that the ringsmay be moved into radial positions if necessary and they will havesuflicient clearance in the sleeve that no interference between therings and the surface of the sleeve will occur during any tilting of therings required or, if the rings should contact the sleeve surface duringtilting, such rings may shift radially at least enough to avoidinterference. While some shifting of the rings radially may occur, theportion 21 on the springs and the projections l8 and I9 will permit thiswithout permitting any disassembly. Different dimensions of stock may behandled by the device since it will be apparent that the rings may havebinding engagement with different sizes of the stock merely by tiltingto different positions. When the sleeve is free from the stock, the lefthand ring may abut against the larger end of the secondary sleeve l4 andthe other ring against parts of the left spring so as to hold the partsassembled with the sleeve. Disassembly may be accomplished by removingthe springs and, if necessary, removing one or more of the rivetedprojections. Finally, it might be said that the rings will be made ofhardened metal so as to avoid unnecessary wear and, in view of the factthat they may rotate or turn, this Wear will be distributedeircumferentially.

The device shown by Figs. 3 and 4 is adapted particularly for handlinground stock, indicated at 30, and, in order to obtain stronger bindingengagement with the stock, rings 3| are employed which have acylindrical surface 32 bored at an angle to the plane of the ring. Inother words, the axis of the outer periphery of the ring is at a slightangle to the axis of the surface 32. Projections 33 and 34 at the upperside of the ring hold it in axial position and these are riveted to thesleeve in the manner previously indicated. For preventing rotation ofthe ring,

its upper portion has a radial slot 35 at one side which receives theprojection 34, and it should be understood that this slot will be ofsuch character that tilting of the ring will be permitted, while stillobtaining axial anchoring, so that movement of the sleeve will effectaxial movement of the ring.

At the left side of the ring, a tapered su face 36 is provided so thatthe stock may be guided into the ring and into the cylindrical portion32. Itshould be understood that the diameter of the cylindrical portion32 may be varied and that normally the diameter will be at leastslightly greater than the stock diameter so as to obtain bindingengagement at the left hand lower edge of the surface and at the righthand upper edge thereof. The variation in diameter should be such as toallow variations in stock dimensions, while still enabling the rings tobind securely against the stock. Spring elements 2|, which are the sameas already described, may be -em ployed for biasing the rings to tiltedpositions. In this case, as in the previous design, the rings willimmediately bind against the stock when the sleeve is moved to theright, while they will tilt into non-binding positions upon moving thesleeve to the left. Finally, it might be said that the axis of thecylindrical surface 32 and the axis of the outer periphery of the ringwill lie in a vertical plane or in the plane of the paper. as seen inFig. 3. In other words, if the ring is in the position shown in Fig. 3,a boring tool to form the surface 32 must be tilted vertically from aposition axially coinciding with the axis of the ring, This is mentionedparticularly so that it will be understood how the cylindrical surfaceis related to the ring with the latter held against rotation.

Each device may be manufactured inexpensively and assembled easily. Withthe rings constructed of hardened metal, it will be apparent that eachdevice will have long life and, in view of the repeated use of thesedevices in the operation of automatic screw machines, long life andefficient operation are definitely desirable.

Although more than one form of the invention has been described andillustrated in detail, it will be apparent to thos skilled in the artthat various modifications may be made without departing from the spiritof the invention.

What is claimed is:

1. A stock pusher for an automatic screw ma- V chine or the likecomprising a sleeve adapted to be shifted axially in on direction tomove the stock and to be shifted idly in the other direction, a ringdisposed transversely in the sleeve and through which the stock is toextend. the inner periphery of the ring being adapted to have bindingengagement with the stock when the latter is tilted, means anchoring thering on the sleeve at one point so that it may tilt and bindingly engagethe stock while being axially moved by the sleeve, and a generally Vshape wire spring element having the ends of its legs respectivelyanchored on the sleeve and engaging the ring at a location generallyopposite said anchoring means, the intermediate portion of the springbeing bowed circumferentially of the sleeve so that the wire extendscircumferentially of the sleeve first in one direction along the innersurface of the latter and then reversely in the other air cumf'erentialdirection.

2. A stock pusher for an automatic screw maanchored to the sleeve innersurface at one point and having side portions extendingcircumferentially in opposit directions, each side portion terminatingin a circumferentially reversed portion to define a, loop disposed in acylindrical segment adjacent the sleeve surface, the ends of such loopportions remote to th wire anchoring point, engaging the ring at a pointgenerally opposite the ring anchoring means.

CASS S. KASPER.

